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Expression, Purification, and Antimicrobial Activity of S100A12
Published on: May 13, 2017
Marjoram extract down-regulates the expression of Pasteurella multocida adhesion, colonization and toxin genes: A
Marwa I Abd El-Hamid1, M E El-Sayed2, Aisha R Ali3
1Department of Microbiology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
Abstract:
Due to the emergence of virulent and antibiotic-resistant microbes, natural antimicrobials from herbal origins have been given more attention as an alternative therapy. This study provides an in vitro research framework to investigate the antibacterial activities of 5 herbal (marjoram, garlic, onion, cinnamon and black seed) oil extracts against 16 multidrug-resistant (MDR) and virulent P. multocida serogroup A isolates recovered from dead and clinically diseased rabbits. Pathogenicity of the screened isolates was further proven experimentally and was verified by PCR analyses of 5 randomly selected virulence genes encoding attachment and colonization proteins (ptfA, pfhA, and omp87), sialidases (nanB) and dermonecrotoxin (toxA). A total of 12 P. multocida isolates were highly pathogenic with the possession of all examined virulence genes, while the other 4 isolates were of lower pathogenicity with expression of the target genes except toxA. In vitro anti-P. multocida activities of the 5 extracts and their synergism rates with 4 antibiotic drugs revealed that marjoram and cinnamon extracts had the highest antibacterial activities and the highest synergism rates against the screened isolates. Pasteurella multocida virulence gene expression profiles were assessed via real-time quantitative reverse transcription PCR (qRT-PCR) in response to marjoram extract. The quantitative analyses showed less than five-fold reduction in the targeted virulence genes expression in presence of marjoram extract compared with the control. The findings from this study document a novel molecular inhibitory activity of marjoram against P. multocida multiple virulence genes and provide a proof of concept for its implementation as an alternative candidate for the treatment of pasteurellosis in farm animals in future.
Insights
Marjoram and cinnamon extracts show potent antibacterial activity against multidrug-resistant *Pasteurella multocida*. Marjoram extract also inhibits key virulence genes, offering a potential alternative therapy for pasteurellosis in farm animals.
Area of Science:
- Veterinary Microbiology
- Natural Product Chemistry
- Antimicrobial Resistance
Background:
- Emergence of virulent and antibiotic-resistant microbes necessitates alternative therapies.
- Herbal antimicrobials are gaining attention as potential treatments.
- Focus on *Pasteurella multocida* (P. multocida) as a significant pathogen in rabbits.
Purpose of the Study:
- To investigate the in vitro antibacterial activities of five herbal oil extracts against multidrug-resistant (MDR) *P. multocida*.
- To evaluate the synergistic effects of these extracts with antibiotics.
- To assess the impact of marjoram extract on *P. multocida* virulence gene expression.
Main Methods:
- In vitro screening of marjoram, garlic, onion, cinnamon, and black seed oil extracts against 16 MDR *P. multocida* isolates.
- Experimental pathogenicity confirmation and PCR analysis of virulence genes (ptfA, pfhA, omp87, nanB, toxA).
- Real-time quantitative reverse transcription PCR (qRT-PCR) to analyze virulence gene expression changes in response to marjoram extract.
Main Results:
- Marjoram and cinnamon extracts exhibited the highest antibacterial activity and synergism with antibiotics against *P. multocida*.
- 12 out of 16 isolates were highly pathogenic, possessing all tested virulence genes.
- Marjoram extract demonstrated a novel inhibitory effect on *P. multocida* virulence gene expression, with less than a five-fold reduction.
Conclusions:
- Marjoram and cinnamon extracts show significant potential as natural antimicrobials against MDR *P. multocida*.
- Marjoram extract possesses a molecular inhibitory activity against *P. multocida* virulence genes.
- This study provides a proof of concept for using marjoram as an alternative treatment for pasteurellosis in farm animals.
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